AP®︎ Biology: Topic 2.4 Practice Test
Prepare for your quiz, test, or the AP exam with focused practice questions on Topic 2.4 of AP Biology – Membrane Permeability.
Questions List
Topic 2.4
Question 1 Easy
This question tests the following: ENE-2.B
What is the primary structure of the plasma membrane?
What You’re Being Tested On:
Explore the learning objectives taken directly from the College Board’s AP® Biology Curriculum. Ensure you’re prepared for the exact topics covered on the AP® exam, in-class tests, and quizzes, and gain confidence in your mastery of the material.
Topic 2.4: Membrane Permeability
Learning Objective: 2.4.A
Explain how the structure of biological membranes influences selective permeability.
Essential Knowledge: 2.4.A.1
Plasma membranes separate the internal environment of the cell from the external environment. Selective permeability is the result of the plasma membrane having a hydrophobic interior.
Essential Knowledge: 2.4.A.2
Small nonpolar molecules, including N2, O2, and CO2, freely pass across the membrane. Hydrophilic substances, such as large polar molecules and ions, move across the membrane through embedded channels and transport proteins.
Essential Knowledge: 2.4.A.3
The nonpolar hydrocarbon tails of phospholipids prevent the movement of ions and polar molecules across the membrane. Small polar, uncharged molecules, like H2O or NH3 (ammonia), pass through the membrane in small amounts.
Learning Objective: 2.4.B
Describe the role of the cell wall in maintaining cell structure and function.
Essential Knowledge: 2.4.B.1
Cell walls of Bacteria, Archaea, Fungi, and plants provide a structural boundary as well as a permeability barrier for some substances to the internal or external cellular environments and protection from osmotic lysis.
